Shoring apparatus



Dec. 21, 1965 J. L. BRUNTON 3,224,201

SHORING APPARATUS Filed Aug. 11, 1960 2 Sheets-Sheet l INVENTOR. James L. Brumon QA AAXXM ATTORNEY Dec. 21, 1965 J. BRUNTON SHORING APPARATUS 2 Sheets-Sheet 2 Filed Aug; 11, 1960 INVENTOR. James L. Brunfon 63 A 71 mm ATTORNEY United States Patent 3,224,201 SHORING APPARATUS James L. Brunton, Yorbalinda, Calif., assignor to Speed Shore Corporation, Gardena, Calif., a corporation of California Filed Aug. 11, 1960, Ser. No. 48,900 Claims. (Cl. 61-41) The present invention relates to a shoring apparatus and more particularly to an apparatus for supporting the walls of a subterranean excavation.

In the excavation of trenches, as to lay pipe lines, it is common practice to shore or support the walls of the excavation to avoid caving. The extent to which the walls of an excavation must be supported is dependent upon the subterranean formation and the nature of the excavation. However, in view of the great danger to personnel in trenches, it is common practice to provide some shoring even in trenches through hard compact ground.

Normally, an excavation is shored with timber uprights with abutt against the walls and are supported by screw jacks or wooden braces fixed between the uprights. The placement and removal of these structures often accounts for a large part of the total cost of a pipeline project. Furthermore, it is usually necessary for workmen to enter the unsupported excavation to assemble the shoring structure so that this is very hazardous work. Conventional shoring structures are thus expensive and still jeopardize human life. Therefore, a need exists for a shoring apparatus which may be economically and safely employed to support the Walls of an excavation.

As any entry into an unshored excavation is dangerous, safe shoring requires a shoring apparatus which may be inserted in an excavation from outside the excavation. Furthermore, it is important that such shoring apparatus remain rigid and tight in the excavation after it has been placed.

To achieve these desirable features, the present invention provides a collapsible shoring apparatus which can be repeatedly used, and which may be placed in an excavation, and removed therefrom while the operator remains out of the excavation. Furthermore, the present invention may be embodied in a unit which can be conveniently handled by one man. In providing a collapsible shoring apparatus which is safe, it is necessary to incorporate lock means to hold the apparatus rigidly in place, so that once the apparatus has been set in position, it will not collapse until it is removed.

In general, the present invention comprises a hydraulic shoring apparatus including a pair of rails to abutt against the walls of an excavation and provide the desired support. The rails are held spaced apart by hydraulic jacks which are pivotally attached to the rails so as to permit the apparatus to be collapsed by folding the jacks between the rails. Force-transfer blocks are affixed between the jacks and the rails to provide positive locking of the apparatus when it is positioned in an excavation. The apparatus also incorporates means for interconnecting the hydraulic jacks, so that each of the jacks may be pressured and relieved through a single valve.

An object of the present invention is to provide an improved shoring apparatus.

Another object of the present invention is to provide a safe, economical shoring apparatus which may be repeatedly used to support the walls of excavations.

Still another object of the present invention is to provide a shoring apparatus which may be placed in supporting position in an excavation, from outside the excavation.

"ice

A further object of the present invention is to provide a collapsible shoring apparatus which has a simple, economical and rugged structure that accomplishes positive locking when inserted in an excavation.

These and other objects and advantages of the present invention will become apparent from a consideration of the following taken in conjunction with the appended drawings wherein:

FIG. 1 is a perspective view of an apparatus constructed in accordance with the present invention;

FIG. 2 is a plan view of the apparatus of FIG. 1 in a partly-collapsed state; and

FIG. 3 is a horizontal sectional view taken along line 3-3 of FIG. 1.

Referring initially to FIG. 1, there are shown a pair of rails 10' and 12 which are general similar, and may be formed of aluminum alloy. The rails (FIG. 3) comprise a flat elongate section 14 having the edges thereof turned inwardly to form edges 16 and 18, and include inward parallel ridges 20 and 22 extending the full length of rail. In general, this structure has been found to be capable of supporting considerable load in proportion to the amount of material in the rail.

The rails 10 and 12 are shown in a position to support the walls of an excavation which abutt against the outside flat surfaces of the rails. The rails are held in an excavation in this position by hydraulic jacks 24 and 26 which are generally similar and will now be considered in detail. In view of the similarity of the jacks, and the method of mounting them, only the jack 26 is considered in complete detail.

The jack 26 is affixed to the rail 12 by a force-transfer block 28 (FIG. 3) which is held between the ridges of the rail 12 by a shaft 30 which extends through the block and the ridges. The shaft 30 is held in position by pins 32 and 34 extending through the ends thereof. Therefore, the block 28 is pivotally attached to the rail 12 and may swing about the shaft 30.

A threaded bore centrally located in the block 28 receives a stud 36 which is in turn telescopically received in a hollow shaft 38 and locked with a pin 40 extending through the combination. The other end of the shaft 38 threadably receives a bolt 40, which passes through a piston 42, a group of seal rings 44, and a slider 46. This structure is slidably fitted in a cylinder 48 which is threadably affixed in a force-transfer block 50. The force transfer block 50 is pivotably mounted on the rail 10 by a shaft 52 extending through the ridges of the rail and a bore in the block. The shaft 52 is held against axial movement by keys 54 and 56. A sealing ring 58 between the cylinder 48 and the block 50 closes the cylinder 48.

It is to be noted that the shaft 32 extending through the block 28 is positioned at the opposite end of the block 28 from which the shaft 52 is positioned in the block 50. Therefore, the block 28 is pivotally movable upwardly, while block 50 is pivotally movable downwardly. As a result of this method of connection of the jacks to the rails, the apparatus may be collapsed by folding the jacks 24 and 26 between the rails 10' and 12. FIG. shows the shoring apparatus partially collapsed in this manner.

The jacks 24 and 26 of the shoring apparatus are interconnected so as to be pressured and relieved through a common quick-connect valve 60 affixed in the block 50. The block 50 also receives a coupling 62 which is connected through a flexible tube 64 to a coupling 66 in the block 50a at the base of the jack 24. It is to be noted, that the flexible tube 64 (FIG. 1) is looped between the couplings 62 and 66. It is this loop of the tube 64 which permits the unit to be collapsed without undue stress and strain on the tube 64, thereby permit ting a flexible tube to be used and avoiding the need for expensive hydraulic plumbing.

In the assembly of the apparatus illustratively shown, the jacks 24-and 26 may be first formed as a subassembly. In this operation, the stud 36 (FIG. 3) is fixed between the block 28 and the shaft 38. Next, the stud 40 is positioned through the piston assembly and turned into the shaft 38. Thereafter, the cylinder 48 is placed in the block 50 and the piston assembly is inserted into the cylinder 48. The apparatus is then completed by aflixing the jacks 24 and 26 between the rails and 12 and interconnecting the jacks with the tube 64. In this regard, as shown in FIG. 1, it is to be noted that the placement of the two jacks 24 and 26 is such that they are spaced apart on the rails by a distance at least one half the total length of the rails. Furthermore, the rail widths are over four times the widths of the jacks.

In using the shoring apparatus as described herein, it is collapsed for transportation to the location of the excavation. The collapsed unit is then held at the edge of the excavation as the operator grasps the handle 21 while standing a safe distance back from the edge of the excavation. The collapsed shoring apparatus is then lowered into the excavation, so that the jack 24 is toward the bottom of the excavation. As the apparatus is lowered, the rail 12 drops to a position in alignment with the rail 10 so that the flat load surfaces of theforcetransfer blocks fully contact flat interior bearing surfaces of the rails. This position of the apparatus is indicated in FIG. 1.

Next, the coupling 60 is connected to a source of hydraulic fluid under pressure so that fluid flows into the cylinders, e.g. cylinder 48, thereby urging the pistons out of the cylinders to spread the rails 10 and 12. As the pressure in the jacks 24 and 26 is substantially balanced the rails 10 and 12 are uniformly spread until the walls of the excavation are encountered and supported. Thereupon, the coupling 60 is disconnected from the source of hydraulic fluid and the apparatus remains rigid to provide the desired support.

It is to be noted, that in view of the structure of the force-transfer blocks, and the manner in which these blocks are pivotally mounted upon the rails 10 and 12, the shoring apparatus is positively locked as a solid unit. Therefore, the application of unbalanced forces to the apparatus may not move or flex any parts which could bend or deform, thereby causing the unit to fail.

Of course, in the excavation of a trench a number of the shoring apparatus are used, and the spacing between them is dependent upon the type formation encountered and the depth of the excavation. However, it is noteworthy that even in trenches which must be heavily shored, a small shoring crew can normally place shoring apparatus of the present invention sufficiently fast to keep pace with the trenching.

Upon the completion of the shoring operation a pipeline or other structure is normally placed in the excavation. Thereafter the shoring apparatus can be rapidly and easily removed by releasing the fluid in the jacks 24 and 26 through the couplings 60. Thereupon, the rail 12 may be raised to collapse the unit and facilitate the removal of the entire apparatus from the excavation. It is to be noted, that raising the rail 12 exerts a compressive force upon the jacks 24 and 25 thereby telescoping these jacks to discharge the hydraulic fluid therefrom. Of course, an inexpensive hydraulic fluid as diesel fluid may be used in the system and simply discharged into the excavation as the shoring apparatus is removed.

In view of the above description, it may be seen that an important feature of the present invention resides in the use of the force-transfer blocks, which facilitate the safe collapsing of the apparatus for easy insertion and removal, as well as storage and transportation. Additionally, this structure results in the desired positive locking of the apparatus during operation.

Also from the foregoing, it will be apparent that the present invention provides an apparatus capable of many variations and modifications consequently the present invention is not to be limited to a particular arrangement as herein shown and described, except as defined in the appended claims.

What is claimed is:

1. A collapsible shoring apparatus for use in trench excavations comprising: first and second elongate rails each having exterior load supporting surfaces and interior bearing surfaces; a first plurality of force transfer blocks each having flat load surfaces and having one upper end pivotally aflixed to said first of said rails along a first axis spaced from said supporting surface thereof, the distance from said supporting surface of said block to said first axis being substantially equal to the distance from said interior bearing surface on said first rail to said first axis to swing relative said first of said rails to one position in which said load surfaces engage said hearing surfaces over their entire area and thereby support the load applied to said load supporting surface of said first of said rails and to another position in which the lower ends of said first blocks are away from said first of said rails; a second plurality of force transfer blocks each having flat load surfaces and having one lower end pivotally aflixed to said second of said rails along a second axis spaced from said supporting surface thereof, the distance from said supporting surface of said block to said second axis being substantially equal to the distance from said interior bearing surface on said second rail to said second axis to swing relative said second of said rails to one position in which said load surfaces engage said bearing surfaces over their entire area and thereby support the load applied to said load supporting surface of said second of said rails and to another position in which the upper ends of said second blocks are away from said first of said rails; a plurality of hydraulic jacks each including a piston and a cylinder, and being affixed between opposed pairs of said first and second force transfer blocks whereby to lie substantially horizontal when said first and second force transfer blocks support load, said jacks and said blocks being aflixed together with said rails so that said first blocks and said second blocks pivotally move in opposite directions upon collapsing or spreading said apparatus.

2. A collapsible shoring apparatus for use in trench excavations comprising: first and second elongate rails having exterior load-supporting surfaces and interior bearing surfaces; a first plurality of force-transfer blocks having load surfaces and having one upper end affixed to the interior surface said first of said rails on a first pivotal axis spaced downwardly from said upper end so that each of said first blocks is movable to a limit position, the distance from said first pivotal axis to said load surface on said first force-transfer blocks being equal to the distance from said first pivotal axis to said interior bearing surfaces on said first rail when said blocks are in said limit position whereby said load surfaces of said first blocks are each in mating engagement with one of said interior bearing surfaces to thereby support the load applied to said first rail; a second plurality of forcetransfer blocks having load surfaces and having one lower end aflixed to said second of said rails on a second pivotal axis spaced upwardly from said lower end and offset from said pivotal axes of said first plurality of force-transfer blocks so that each of said second blocks is movable to a limit position, the distance from said second pivotal axis to said load surface on said second force-transfer blocks being equal to the distance from said second pivotal axis to said interior bearing surfaces on said second rail when said blocks are in said limit position whereby said load surfaces of said second blocks are each in mating engagement with one of said interior bearing surfaces to thereby support the load applied to said second rail; jack means including a piston and a cylinder, atflxed between opposed pairs of said first and second force-transfer blocks with offset pivots so as to hold said load surfaces of said pairs of blocks substantially parallel; said pistons in said jack means having a substantially smaller sectional area than the sectional area of each of said blocks affixed to said jack means; said jack means and said blocks being affixed together with said rails so that said first blocks and said second blocks pivotably swing in opposite directions upon collapsing or spreading said apparatus.

3. A collapsible shoring apparatus for use in trench excavations comprising: first and second elongate rails having load-supporting exterior surfaces and interior surfaces bearing a plurality of ridges respectively parallel the length of said elongate rails; a plurality of spaced apart interior bearing surfaces on each of said rails intermediate said ridges thereon; a first plurality of forcetransfer blocks having load surfaces; first pivot means including plural first pivot pins affixed in said ridges of said first rail and each passing through one of said first blocks whereby to pivotally affix the upper ends of said first blocks to said first of said rails about a first pivotal axis, so that each of said first blocks is movable to a limit position, the distance from said first pivotal axis to said load surface on said first force-transfer blocks being equal to the distance from said first pivotal axis to said interior bearing surfaces on said first rail when said blocks are in said limit position whereby said load surfaces of said first blocks are each in mating engagement with one of said interior bearing surfaces to thereby support the load applied to said first rail; a second plurality of force-transfer blocks having load surfaces, second pivot means including plural second pivot pins aflixed in said ridges of said second rail and each passing through one of said second blocks whereby to afiix the lower ends of said first blocks to said second of said rails about a second pivotal axis, so that each of said second blocks is movable to a limit position, the distance from said second pivotal axis to said load surface on said second force-transfer blocks being equal to the distance from said second pivotal axis to said interior bearing surfaces on said second rail when said blocks are in said limit position whereby said load surfaces of said second blocks are each in mating engagement with one of said interior bearing surfaces to thereby support the load applied to said second rail; a jack affixed between opposed pairs of said first and second force-transfer blocks to hold said pairs of blocks substantially parallel; said jacks and said blocks being afiixed together with said rails by said pivot means so that said first blocks and said second blocks pivotally move in opposite directions upon collapsing or spreading said apparatus.

4. A collapsible shoring apparatus for use in trench excavations comprising: first and second elongate rails having load-supporting exterior surfaces and internal surfaces bearing ridges extending parallel the length of said rails; a plurality of spaced apart interior bearing surfaces on each of said rails intermediate said ridges thereon; a first plurality of force-transfer blocks having load surfaces and having one upper end affixed to said first of said rails by being pivotally connected to said ridges of said first of said rails at a first pivot point spaced downwardly said upper end of said block, so that each of said first blocks is movable to a limit position, the distance from said first pivot point to said load surface on said first force-transfer blocks being equal to the distance from said first pivot point to said interior bearing surfaces on said first rail when said blocks are in said limit position whereby said load surfaces of said first blocks are each in mating engagement with one of said interior bearing surfaces to thereby support the load applied to said first rail; a second plurality of force-transfer blocks having load surfaces and having one lower end affixed to said second of said rails by being pivotally connected to said ridges of said second of said rails at a second pivot point upwardly said lower end of said block, so that each of said second blocks is movable to a limit position, the distance from said second pivot point to said load surface on said second force-transfer blocks being equal to the distance from said second pivot point to said interior bearing surfaces on said second rail when said blocks are in said limit position whereby said load surfaces of said second blocks are each in mating engagement with one of said interior bearing surfaces to thereby support the load applied to said second rail; a hydraulic jack means affixed between opposed pairs of said first and second force-transfer blocks to maintain said pairs of blocks, substantially parallel; said jack means having a substantially smaller sectional area than the sectional area of said blocks affixed to said jack means; said jack means and said blocks being afiixed together with said rails so that said first blocks and said second blocks pivotably move in opposite directions upon collapsing or spreading said apparatus.

5. A shoring apparatus in accordance with claim 4 wherein said rails are substantially wider than said forcetransfer blocks and further comprising means to provide substantially equal fluid pressure in each of said jack means.

References Cited by the Examiner UNITED STATES PATENTS 503,437 8/1893 Pilcher 6139.1 X

587,274 7/1897 Rue 6139.1

785,810 3/1905 Koopman 182-160 1,314,201 8/1919 Moore 182159 2,482,367 9/ 1949 Ravers 6l--41 2,795,935 6/ 1957 Fitzgerald 61-452 2,922,283 l/ 1960 Porter 6l41 3,029,607 4/ 1962 Millerbernd 61-41 FOREIGN PATENTS 641,109 8/ 1950 Great Britain.

CHARLES E. OCONNELL, Primary Examiner.

WILLIAM I. MUSHAKE, JACOB L. NACKENOFF,

Examiners. 

2. A COLLAPSIBLE SHORING APPARATUS FOR USE IN TRENCH EXCAVATIONS COOMPRISING: FIRST AND SECOND ELONGATE RAILS HAVING EXTERIOR LOAD-SUPPORTING SURFACES AND INTERIOR BEARING SURFACES; A FIRST PLURALITY OF FORCE-TRANSFER BLOCKS HAVING LOAD SURFACES AND HAVING ONE UPPER END AFFIXED TO THE INTERIOR SURFACE SAID FIRST OF SAID RAILS ON A FIRST PIVOTAL AXIS SPACED DOWNWARDLY FROM SAID UPPER END SO THAT EACH OF SAID FIRST BLOCKS IS MOVABLE TO A LIMIT POSITION, THE DISTANCE FROM SAID FIRST PIVOTAL AXIS TO SAID LOAD SURFACE ON SAID FIRST FORCE-TRANSFER BLOCKS BEING EQUAL TO THE DISTANCE FROM SAID FIRST PIVOTAL AXIS TO SAID INTERIOR BEARING SURFACES ON SAID FIRST RAIL WHEN SAID BLOCKS ARE IN SAID LIMIT POSITION WHEREBY SAID LOAD SURFACES OF SAID FIRST BLOCKS ARE EACH IN MATING ENGAGEMENT WITH ONE OF SAID INTERIOR BEARING SURFACES TO THEREBY SUPPORT THE LOAD APPLIED TO SAID FIRST RAIL; A SECOND PLURALITY OF FORCETRANSFER BLOCKS HAVING LOAD SURFACES AND HAVING ONE LOWER END AFFIXED TO SAID SECOND OF SAID RAILS ON A SECOND PIVOTAL AXIS SPACED UPWARDLY FROM SAID LOWER END AND OFF SET FROM SAID PIVOTAL AXIS OF SAID FIRST PLURALITY OF FORCE-TRANSFER BLOCKS SO THAT EACH OF SAID SECOND BLOCKS IS MOVABLE TO A LIMIT POSITION, THE DISTANCE FROM SAID SECOND PIVOTAL AXIS TO SAID LOAD SURFACE ON SAID SECOND FORCE-TRANSFER BLOCKS BEING EQUAL TO THE DISTANCE FROM SAID SECOND PIVOTAL AXIS TO SAID INTERIOR BEARING SURFACES ON SAID SECOND RAIL WHEN SAID BLOCKS ARE IN SAID LIMIT POSITION WHEREBY SAID LOAD SURFACES OF SAID SECOND BLOCKS ARE EACH IN MAT- 